Isoquinolone derivatives



United States Patent ISOQUINOLONE DERIVATIVES Merrill Eugene Speeter, Kalamazoo, Mich., assignor to Bristol Laboratories Inc., Syracuse, N. Y., a corporation of New York No Drawing. Applicafion February 18, 1953, Serial No. 337,658

6 Claims. (Cl. 260-2475) This invention relates to a .new class of organic compounds and methods of preparation thereof, More particularly, the invention relates to a series of substituted 2-alkyl-4-phenyl-1,2,3,4 tetrahydro-3-isoquinolones.

The new compounds include free bases, acid addition salts and quaternary salts, whose free 'bases may be represented by the following general formula:

wherein .R represents a lower alkyl radical containing one to six carbon atoms, X represents an alkyleneradical containing two to four carbon atoms inclusive andB represents di-(lower aIkyD-amino, piperidino, morpholino, pyrrolidino, N'-a1kylpiperazino or pipecolino.

The compounds of this invention are useful in medicine as anti-spasmodic agents. The free bases 'and acid addition salts are useful :as intermediates in the preparation of the quaternary salts; the quaternary salts are useful as germicides and disinfectants.

The compounds of this invention are prepared by reacting 2-alkyl-4-phenyl-l;2,3,4 tetrahydro-3-isoquino1ones, whose preparation is described in my co-pending :appli cation Serial Number 337,657, filed February '18, 1953, now abandoned, with lithium amide to form the lithioderivatives and then reacting this 'lithio derivative with :the appropriate alkyl-aminoalkyl halide.

The 2-a1ky1-4-phenyl-1,2,3,4-tetral1ydro-3-isoquinolones used as starting materials are prepared by reacting ibenzylamine or secondary benzylamines with tacetylmandel-ylanilides-to give O-aceta1 N-b.enzylmandelamideswhichare reacted with sulfuric acid to give 4-phenyl-1:,2,3,4-tetrahydro-S-isoquinolones according to the following acquation wherein R represents lower r-allcyl containing one to six carbon atoms.

A specific example of the preparation of starting material of this'isype is as :follows:

A. fO-acetyl-N-benzyLN +mer71y'lmandelamide.- lo a solution of 182.8 g. (:1 rmol) rof 'N-imethyl ben-zylamine in .1200 ml. of .dry benzene .is :added 2159 :(0.75 mole.) of acetylmandelyl chloride \dro pwise with shaking. The mixture is allowed .to stand at room :temperature tor three Patented Aug- .21, 1956 hours and is then refluxed for three hours. The precipitate of vamme hydrochloride is collected by filtration, washed with benzene and discarded. The filtrates and washings are combined and shaken with dilute hydrochloric acid and then with water. The dried toluene solution is distilled and the residue crystallized. The crystals obtainedmelt at "97.5""99" C. after two recrystallizations from isopropyl alcohol.

Analysis-Calculated for CuiHmNOa-z :Oalculated- Found The following examples will serve to illustrate the invention without limiting it thereto.

Nineteen grams (0.08 mole) of 2-methyl-4-phenyl- 1,2,3,4-tetrahydroe3-isoqnino1one is refluxed .for two hours with 3.45 g. (0.15 mole) of lithium amide in 250 m1. of dry toluene. A solution of 21.7 'g. (0.15 mole) of piperidylethyl chloride is added in 290 ml. tot toluene and the mixture refluxed for eighteen hours. The cooled mixture is poured into waterand the toluene layer separated. The toluene layer is extracted with dilute hydrochloric acid. The acid extracts are cooled and made 'tbasic with ammonium hydroxide. heoil thus liberated from {the :acid extracts is extracted "from ether. The ether :is removed by distillation, leaving the product as the .free base. Addition of sulfuric acid to a solution of the oil in isopropyl alcohol gives the sulfate salt. The salt crystal lizes from isopropanol and melts at 241 242 C.

Analysis.Calculated for (Baal-IzsNzO -H2SO4:

Calculated Found o V 3 261.78 I 62.10 H r 6.77 I 6.60

2-methyl-4ephenyll-piperidylethyl-i ,'2,3,4-.te traihydro- 3-isoqui-nolone methiodide .Analysis.-Calculated for Cml-laiNaQl --CHsO,H:

L Galcula'ted Found EXAMPLE II 2-.ethyl-4 -.phenyZ-4 ;fi-1 ,pipe ridylelh yl-l ,2 ,4- tetrahydroJ-isoguinolone The lithio derivative of LZ-ethyl-A-phenfl-1,2,3.4-tetrahydro-.Bdsoquinolone is reacted with piper'idylethyl chloride according to the procedure set forth in detail Example l .to give as a product the frceibase 2-ethyl-4-phenyl- 4-.piperidylethyl-1,2,;3,4-tetra;hydro-3-isoquinolone, which remains :behind after concentration by distillation of its ethereal solution. This free base is converted to quaternary and acid addition salts by treatment with ethyl iodide and dilute, alcoholic hydrochloric acid respectively.

EXAMPLE III Z-methyl-4-phenyl-4-fl-morpholinylethyl-1,2,3,4- tetrahydro-3-isoquin0lone Analysis-Calculated for CzzHzsNzOz:

Calculated I Found O 75. 40 75. 35 H 7. 4s 7. 33

This free base is converted to quaternary and acid addition salts by treatment with excess n-propyl iodide and dilute, alcoholic citric acid respectively.

EXAMPLE IV 2-n-pr0pyl-4-phenyl-4-B-m0rph0linylethyl-1,2,3,4- tetrahydro-3-isoquinolone Following the procedure of Example I and using quantities of the reagents in the same molar ratio as therein, 2-n-proyl-4-phenyl-l,2,3,4-tetrahydro-3-isoquinolone is reacted first with lithium amide and then with p-morpholinylethyl chloride to give as a product the free base, 2 n propyl 4 phenyl 4 ,3 morpholinylethyl- 1,2,3,4-tetrahydro-3-isoquinolone. This free base is converted to quaternary and acid addition salts by treatment with benzyl chloride and dilute, alcoholic tartaric acid respectively.

EXAMPLE V 2-methyl-4-phenyl-4-dimethylaminoethyl-I,2,3,4-tetrahydr-3-is0quin0lone Twenty grams of 2-methyl-4-phenyl-1,2,3,4-tetrahydro- 3-isoquinolone is reacted with lithium amide and with dimethylaminoethyl chloride using the molar ratios and experimental procedure disclosed in Example I. The product is isolated as the free base and purified by distillation-in vacuo, B. P. l87-l99 C./28-30 microns.

Analysis-Calculated for C2oH24N2O:

Calculated Found This free base is converted to quaternary and acid addition salts by treatment with n-butyl bromide and dilute, alcoholic phosphoric acid respectively.

EXAMPLE VI EXAMPLE VII 2-methyl-4-phenyl-4-diethylaminoethyl ],2,3,4 tetrahydr0-3-is0quirz0lone The procedure of Example I is followed, with the piperidylethyl chloride replaced by diethylaminoethyl chloride. The product, 2-Inethyl-4-phenyl4-diethylaminoethyl-l,2,3,4-tetrahydro-3-isoquinolone, is isolated as the free base and purified by distillation in vacuo (B. P. 2l6-22l C./2.5 mm.).

Analysis.-Calculated for CzzHzaNzO:

Calculated Found CL 78.54 78.70 H. s. 39 7.

The free base is converted to quaternary and acid addition salts by treatment with l-bromo-Z-ethylhexane and dilute, alcoholic acetic acid respectively.

EXAMPLE VIII 2 is0-butyl-4-phenyl 4 dielhylaminoethyl 1,2,3,4-

tetrahydro-3-isoquinolone The procedure of Example I is followed, using 2-isobutyl 4 phenyl-1,2,3,4-tetrahydro-3-isoquinolone and diethylaminoethyl chloride. The product, 2-iso-butyl-4- phenyl-4 diethylaminoethyl l,2,3,4 tetrahydro-3-isoquinolone, is isolated as the free base, purified by distillation in high vacuum and converted to quaternary and acid addition salts by treatment with isobutyl bromide and dilute, alcoholic succinic acid respectively.

The invention also includes the non-toxic organic and inorganic acid addition salts of the compounds having the general formula above such as will be readily formed with, for example, organic and inorganic acids such as hydrochloric, sulfuric, sulfamic, tartaric, hydrobromic, hydriodic, glycolic, citric, maleic, phosphoric, succinic, acetic, benzoic, cinnamic, mandelic, malic, ascorbic, and the like. The method of preparation of these salts is made apparent in the examples above.

This invention also contemplates the quarternary salts .of the free bases of the general formula above, which may be prepaired as made apparent in the examples above by treatment of the free bases with quaternary salt-forming substances. These quaternary salt-forming substances include methyl chloride, methyl bromide, methyl iodide, ethyl chloride, ethyl bromide, ethyl iodide, n-propyl chloride, n-propyl bromide, n-propyl iodide, isopropyl bromide, n-butyl chloride, n-butyl bromide, isobutyl bromide, sec.-butyl bromide, n-amyl bromide, n-hexyl chloride, benzyl chloride, benzyl bromide, methyl sulfate, ethyl sulfate, methyl benzenesulfonate, methyl p-toluenesulfonate, etc. which Will react directly with any free base of the general formula above to give respectively the methochloride, methobromide, methiodide, ethochloride, ethobromide, ethiodide, n-propochloride, n-propobromide, n-propiodide, isopropobromide, n-butochloride, n-butobromide, isobutobromide, sec.-butobromide, n-amobromide, n-hexochloride, benzochloride, benzobromide,

propyl bromide, beta-dipropylaminoethyl iodide, gammadipropylaminopropyl iodide, beta dibutylaminoethyl chloride, gamma-dibutylaminopropyl bromide, beta-lpiperidylethyl chloride, gamma-l-piperidylpropyl bromide, beta 1 a pipercolylethyl chloride, gamma 1 'y pipecolylpropyl bromide, beta 1 pyrrolidylethyl chloride, gamma l pyrrolidylpropyl bromide, beta- 1-(4-rnethylpiperazyl)ethyl chloride, gamma-1-(4-ethylpiperazyl)propyl bromide, beta-l-morpholinylethyl chloride, gamma-(l-morpholinyl)propyl bromide, beta-dimethylamino-n-propyl chloride, beta l piperidyl-npropyl bromide, beta-l-morpholinyl-n-propyl chloride, beta-diethylamino a methylethyl chloride, beta-1- (4-methylpiperazyl)-u-methylethyl chloride, beta-di-npropylamino-a,,B-dimethylethyl chloride, beta-l-y-pipecolyl-a,/3dimethyl-ethyl chloride, beta dimethyl-aminon-butyl bromide, beta-l-pyrrolidyl-n-butyl bromide etc. according to the procedures given in detail in the examples above.

Thus, the lithio derivatives of the substituted 4-phenyl- 1,2,3,4-tetrahydro-3-isoquinolones of the second preceding paragraph may be employed, for example, as follows: 2-methyl-4-phenyl-l,2,3,4-tetrahydro-3-isoquinolone with beta 1 (4 methylpiperazyl) a methyl-ethyl chloride to give 2 methyl 4 phenyl 4 [beta-1 (4- methylpiperazyl) a methyl ethyl] 1,2,3,4 tetrahydro 3 isoquinolone, 2 methyl 4 phenyl 1,2,3,4- tetrahydro 3 isoquinolone with beta 1 pyrrolidyln-butyl bromide to give 2-methyl-4-phenyl-4- [beta-(1- pyrrolidyl) n butyl] 1,2,3,4 tetrahydro 3 isoquinolone, 2 ethyl 4 phenyl 1,2,3,4 tetrahydro- 3 isoquinolone with beta dimethylamino n butyl bromide to give 2 ethyl 4 phenyl 4 [beta dimethylamino n butyl] 1,2,3,4 tetrahydro 3 isoquinolone, 2 ethyl 4 phenyl 1,2,3,4 tetrahydro-3- isoquinolone with beta 1 'y pipecolyl a,,8 dimethylethyl chloride to give 2 ethyl 4 phenyl 4 [beta- 1 'y pipecolyl 1, 3 dimethyl ethyl] 1,2,3,4 tetrahydro 3 isoquinolone, 2 isopropyl 4 phenyl 1,2,3,4 tetrahydro 3 isoquinolone with beta di npropylamino :,[3 dimethyl ethyl chloride to give 2- isopropyl 4 phenyl 4 [beta di 11 propylaminoa,,6 dimethyl ethyl] 1,2,3,4 tetrahydro 3 isoquinolone, 2 isopropyl 4 phenyl l,2,3,4 tetrahydro- 3 isoquinolone with beta 1 morpholinyl n propyl chloride to give 2 isopropyl 4 phenyl 4 (beta 1- morpholinyl n propyl) 1,2,3,4 tetrahydro 3 isoquinolone, 2 n propyl 4 phenyl 1,2,3,4 tetrahydro 3 isoquinolone with gamma (1 morpholinyl)- propyl bromide to give 2 n propyl 4 phenyl 4 [gamma (1 morpholinyl)propyl] 1,2,3,4 tetrahydro 3 isoquinolone, 2 n propyl 4 phenyl 1,2,34- tetrahydro 3 isoquinolone with gamma 1 (4 ethylpiperazyDpropyl bromide to give 2 n propyl 4 phenyl 4 [gamma 1 (4 ethylpiperazyl) propyl]- l,2,3,4 tetrahydro 3 isoquinolone, 2 isoamyl 4- phenyl l,2,3,4 tetrahydro 3 isoquinolone with beta- 1 (4 methylpiperazyl) ethyl chloride to give 2 isoamyl- 4 phenyl 4 [beta 1 (4 methylpiperazyl)ethyl]- l,2,3,4 tetrahydro 3 isoquinolone, 2 n amyl 4- phcnyl l,2,3,4 tetrahydro 3 isoquinolone with gamma l pyrrolidylpropyl bromide to give 2 n amyl- 4 phenyl 4 [gamma (1 pyrrolidyl) propyl] 1,2,3,4 tetrahydro 3 isoquinolone, 2 isohexyl 4- phenyl l,2,3,4 tetrahydro 3 isoquinolone with betadiethylamino 0c methyl ethyl chloride to give 2 isohexyl 4 phenyl 4 [beta diethylamino a methylethyl] 1,2,3,4 tetrahydro 3 isoquinolone, 2 betaethyl n butyl 4 phenyl 1,2,3,4-tetrahydro 3- isoquinolone with gamma dipropylaminopropyl iodide to give 2 (beta ethyl n butyl) 4 phenyl 4- [gamma dipropylamino propyl] 1,2,3,4 tetrahydro- 3 isoquinolone, etc. in accordance with the detailed directions of the examples above.

I claim:

1. A member selected from the group consisting of compounds having the structure C=C n-n H/ \H wherein R represents a lower alkyl radical containing one to six carbon atoms, X represents an alkylene radical containing two to four carbon atoms inclusive and B represents a member selected from the group consisting of di-(lower)-alkyl-amino, piperidino, morpholino, pyrrolidino, and pipecolino; and acid addition salts and quaternary salts of said compounds.

2. 2 methyl 4 phenyl 4 B piperidylethyl- 1,2,3,4 tetrahydro 3 isoquinolone.

3. 2 methyl 4 phenyl 4 ,8 piperidylethyl- 1,2,3,4 tetrahydro 3 isoquinolone methiodide.

4. 2 methyl 4 phenyl 4 p morpholinylethyl- 1,2,3,4 tetrahydro 3 isoquinolone.

5. 2 methyl 4 phenyl 4 p dimethylaminoethyl- ,1,2,3,4 tetrahydro 3 isoquinolone.

6. 2 methyl 4 phenyl 4 ,3 diethylaminoethyll,2,3,4 tetrahydro 3 isoquinolone.

No references cited. 

1. A MEMBER SELECTED FROM THE GROUP CONSISTING OF COMPOUNDS HAVING THE STRUCTURE 